Question: There is a 100 pound watermelon laying out in the sun. 99 percent of the watermelon's weight is water. After laying out for a few hours 98 percent of the watermelon's weight is water.
How much water evaporated?
Answer: 50 pounds.
In the beginning it is 99 pounds water and 1 pound other stuff. At the end the 1 pound other stuff is 2 percent so the total weight is 50 pounds. 50 pounds - 1 pound other stuff = 49 pounds water. So 99 pounds - 49 pounds = 50 pounds water lost.
Question: At low tide 14 rungs of a ship are above the water, the rungs are 15 centimeters apart. each 15 mins the water rises 15 centimeters. after 2 hours and 30 mins how many rungs are above the water?